The invention starts with a gear drive unite, in particular for adjusting moveable parts in a motor vehicle.
A drive device for a windshield wiper system of a motor vehicle, which features a housing and an armature shaft positioned rotatably therein that has a worm, became known with DE 198 545 35 A1. Using an axial force generating device, a wedge slider is hereby displaced radially to the armature shaft in order to equalize the axial play of the armature shaft. The displacement force of the wedge slider is applied via a pre-stressed spring element, which presses the wedge slider radially against a limit stop of the armature shaft, thereby displacing the shaft axially until the axial play is equalized. On the other hand, with a great load to the armature shaft via a driven gear, an axial force occurs, which presses the armature shaft against the wedge slider and in doing so the wedge slider is pressed back radially away from the armature shaft against the spring element. This type of great permanent load on the spring element leads to a situation where its service life or its elastic properties are diminished and therefore the axial play of the armature shaft is no longer equalized so that it moves back and forth axially under load, which can produce unpleasant clicking noises.